A liquid crystal display device (LCD) conventionally includes an array substrate, a counter substrate, and a liquid crystal layer as a light modulating layer interposed between these substrates. The liquid crystal display device is broadly divided into a transmissive type, a reflective type, and a semi-transmissive type as a combination of the transmissive type and the reflective type. In the transmissive type, light irradiated from a back surface side (rear surface side) of an array substrate corresponding to a non-display side thereof using a backlight unit is caused to pass through the display device, thereby displaying an image. In the reflective type, light entering the display device from a display side of a counter substrate, specifically a front surface side thereof, is reflected on a pixel electrode provided to an array substrate, thereby displaying an image.
In the liquid crystal display device, a thin film transistor to drive the pixel electrode is located on a back surface side of the pixel electrode. In light of this configuration, in the case of the transmissive type or semi-transmissive type liquid crystal display device, part of light emitted from the backlight unit located on the back surface side of the array substrate and entering the array substrate is likely to enter the thin film transistor. This entry of light causes light leakage that brings about flicker or the like, leading to reduction in display quality in some cases. By contrast, in the case of the reflective type liquid crystal display device, only the extraneous light enters the display device from a front surface side thereof. Thus, the reflective type liquid crystal display device has conventionally been considered not to permit entry of light into the thin film transistor easily and therefore light leakage has been considered unlikely in this display device.
However, recently, even in reflective type liquid crystal display devices, it has been recognized that light leakage into the thin film transistor may occur in some cases. Thus, suppressing entry of extraneous light into the thin film transistor has been desired even in reflective type liquid crystal display devices.